Apparatus for running casing into a well



Sept. 27, 1955 H. H. ADDISON APPARATUS FOR RUNNING CASING INTO A WELL Filed Aug. 23, 1954 United States Patent O APPARATUS FOR RUNNING CASING INTO A WELL Herman H. Addison, Denver City, Tex., assignor to The Texas Company, New York, N. Y., a corporation of Delaware Application August 23, 1954, Serial No. 451,643 6 claims. (C1. 16s- 90) This invention relates broadly to oil well drilling and more particularly to an apparatus for running casing into a well in which uid such as water or drilling uid is present.

Drilling a well by the rotary system necessitates the use of drilling fluid which is introduced into the well through the drill stem. The circulating iluid carries drill cuttings from the bottom of the well to the surface, thereby minimizing the possibility of freezing the drill stem, absorbs functional heat generated in the drill stem and bit, and performs various other functions. The properties of a drilling fluid can be controlled to render it suitable for satisfactory performance.

The presence of uid customarily present in a well during the drilling operation, presents certain problems to the drilling crew when running casing into the well. After the conductor casing has been set and suitably cemented in place at the upper end of the well andthe drill stern withdrawn from the hole, the second or water string of casing is run into the hole as rapidly as possible. The first joint of casing lowered into the well is provided at its lower end with a valved casing shoe which prevents the entry of well fluid into the casing so that the casing can be floated in. Additional joints of casing are added, joint by joint, until the shoe on the lower end reaches the bottom of the well. Lowering of the string through the nid in the well commonly is facilitated by owing into the casing sufficient mud laden fluid to partially overcome the buoyancy of the fluid in the well while at the same time utilizing that buoyancy to relieve some of the strain on the surface equipment.

One object of the present invention is to provide an apparatus for introducing predetermined quantities of drilling mud into a Well casing as successive joints of the casing are added to the string to partially overcome the buoyancy of the fluid in the well.

Another object of the invention is to provide an apparatus of the type mentioned by means of which track can be kept of the amount of mud introduced into the string, and the mud level in the string ascertained at any time with a high degree of accuracy.

Other objects, features and advantages of the invention will appear from the following description and by reference to the accompanying drawings in which:

Figure 1 is a view in elevation of a conventional type of oil well derrick showing the location of the apparatus on the derrick floor; and

Figure 2 is an enlarged view of the same apparatus.

In the drawing there is illustrated a portion of an oil Well derrick, indicated generally by the numeral 10. The derrick shown is of conventional design and has a floor 12 upon which rests the apparatus which constitutes the subject matter of the present invention. A reservoir (not shown) in which an adequate supply of mud laden uid is maintained, is located in close proximity to the derrick.

A receptacle, preferably a joint of pipe or casing 14 adapted to hold a quantity of drilling mud equal in volume to the volume of each of the several joints of casing 2,718,925 Patented Sept. 27, 1955 ICC being run into the well is stood on end in one corner of the derrick on the derrick floor 12, its upper end being maintained in position by means of supporting cables 16 secured at one end to rings 18 on the extreme upper end of the casing and at their opposite ends to the derrick frame. The lower end of the casing 14, which is closed by a plate 20, is provided with one or more adjusting nipples 22 by means of which the height of the casing above the derrick floor ca n be adjusted.

Mud is introduced into the casing 14 through a pipe 24 which connects at one end with the lower end of the casing at a point immediately above the plate 20 and at the other end with a pump 26 which draws mud from the mud reservoir and forces it through the pipe into the casing.

The upper end of the casing is provided with a check valve 28 which is adapted to admit air to the casing 14 while preventing mud from owing out of the casing as it is pumped therethrough. An overow pipe 30 also connects at one end with the upper end of the casing 14 and extends back to the mud reservoir so that any overflow of mud is returned to the reservoir.

A till pipe 32 which has intermediate its ends a nipple 34 by means of which its length can be varied, is swivelly connected at one end to the lower end of the casing 14. The opposite end which is turned at an angle of approximately is adapted to be swung downwardly until its free open end is directly above one of the sections of casing 36 being run into the well so that the mud content of the casing 14 can be dumped into the casing 36.

A plug valve 3S is provided in the fill pipe 32 near its turned end by means of which the ilow of mud through the pipe can be controlled. A counterbalance 40 is attached to the ll pipe near its outer free end by means of a cable 42 operating through a pulley 44 mounted on the casing 14.

In operation, the pump 26 is first started thereby drawing mud from the reservoir and forcing it into the casing 14 through the inlet pipe 24. Mud continues to rise in the casing until it is completely filled. As the pumping continues, excess mud overflows into the overtlow pipe 30 through which it returns to the reservoir. As each successive joint of casing is run into the well, the mud content of the casing 14 is dumped into the well casing. This is accomplished by swinging the fill pipe 32 downwardly until its free end is directly over the upper end of the Well casing. The plug valve 38 is then opened to permit the mud in the casing 14 to gravitate and flow through the fill pipe 32 into the well casing, the check valve 28 opening to admit air to the casing. During the intervals while the mud in the casing 14 is being dumped into the well casing operation of the pump 26 is discontinued but operation is resumed as soon as the valve in the fill pipe is closed.

The filling operation is continued until the desired buoyancy of the string of well casing has been reached and by keeping track of the number of times the contents of the casing 14 are dumped into the well casing it is possible to easily calculate the amount of mud which has been introduced into the string and the mud level in the string, the capacity of the casing 14 being equal to a joint of the well casing.

Obviously, many modiications and variations of the invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

I claim:

l. Apparatus for introducing a predetermined quantity of drilling mud from a mud reservoir into successive joints of well casing as they are run into a bore hole, comprising a receptacle adapted to contain a quantity of mud equal in volume to the volume of each of the several joints of Well casing, means for pumping mud into said receptacle to the limit of its capacity, and means through which the mud content of the receptacle is intermittently drawn from Asaid vreceptacle and dumped into a joint of well casing as it is being run into the bore hole.

2. Apparatus for introducing a predetermined quantity of drilling mud from a mud reservoir into successive joints of well casing as they are run into a bore hole, comprising a receptacle adapted to contain ay quantity of mud equal in volume to the volume of each of the several joints of well casing, means for pumping mud into said receptacle to the limit of its capacity, means through which the mud content of the receptacle is intermittently drawn from said receptacle and dumped into a joint of well casing as it is being run into the bore hole, and an overflow pipe connecting at one end with the upper end of the receptacle through which excess mud is returned to the mud reesrvoir.

3. Apparatusfor introducing a predetermined quantity of drilling mud from a mud reservoir into successive joints of well casing as they are run into a bore hole, comprising a receptacle adapted to contain a quantity of mud equal in volume to the volume of each of the several joints of well casing, means for pumping mud into said receptacle to the limit of its capacity, and a ill pipe swivelly connected at one end to the lower e'nd of the receptacle and adapted to be moved to position its free end directly above one of the sections of well casing being run into the bore hole, and a valve in said fill pipe for controlling the passage of mud from said receptacle to said casing.

4. Apparatus for introducing a predetermined quantity of drilling mud from a mud reservoir into successive joints of well casing as they are run into a bore hole, comprising a receptacle adapted to contain a quantity of mud equal in volume to the volume of each of the several joints of well casing, means for pumping mud into said receptacle to the limit of its capacity, means through which the mud content of the receptacle is intermittently drawn from said receptacle and dumped into a joint of well casing as it is being run into the bore hole, and a check valve in the upper end of said receptacle for admitting air thereto as the mud therein is dumped into said well casing. Y

5. Apparatus for introducing a predetermined quantity of drilling mud from a mud reservoir into successive joints of well casing as they are run into a bore hole, comprising a receptacle adapted to contain a quantity of mud equal in volume to the volume of each of the several joints of well casing, means for pumping mud into said receptacle t'o the limit of its capacity, and a ll pipe swivelly connected at yone `end to the lower end of the receptacle and adapted to be moved to position its free end directly above one of the sections of well casing being run into the bore hole, and a counterbalance operatively connected to said lill pipe.

6. Apparatus for introducing a predetermined quantity of drilling mud from a mud reservoir into successive joints of Well casing as they are run into a bore hole, comprising a lreceptacle adapted to contain a quantity of mud equal volume to the volume of each of the several joints f well casing, means for pumping mud intol said receptacle t the limit of its capacity, a valved ll pipe swivelly connected at one end to the lower end of the receptacle and adapted to be moved to position its free end directly above one of the sections of well casing being run into the bore hole, and a counterbalance operatively connected to said ll pipe.

Draper et al Dec. 24, 1872 Thurber May 13, 1879 

1. APPARATUS FOR INTRODUCING A PREDETERMINED QUANTITY OF DRILLING MUD FROM A MUD RESERVOIR INTO SUCCESSIVE JOINTS OF WELL CASING AS THEY ARE RUN INTO A BORE HOLE, COMPRISING A RECEPTACLE ADAPTED TO CONTAIN A QUANTITY OF MUD EQUAL IN VOLUME TO THE VOLUME OF EACH OF THE SEVERAL JOINTS OF WELL CASING, MEANS FOR PUMPING MUD INTO SAID RECEPTACLE TO THE LIMIT OF ITS CAPACITY, AND MEANS THROUGH WHICH THE MUD CONTENT OF THE RECEPTACLE IS INTERMITTENTLY DRAWN FROM SAID RECEPTACLE AND DUMPED INTO A JOINT OF WELL CASING AS IT IS BEING RUN INTO THE BORE HOLE. 